* add test
* return validation error not nil from function
Closes#665
Reviewed-on: https://gitea.com/gitea/act_runner/pulls/683
Reviewed-by: techknowlogick <techknowlogick@noreply.gitea.com>
Co-authored-by: Christopher Homberger <christopher.homberger@web.de>
Co-committed-by: Christopher Homberger <christopher.homberger@web.de>